1. Field of the Invention
The present invention relates generally to devices and systems for the treatment of air pollution, and particularly to a catalytic converter for confined areas, such as tunnels, parking garages, and the like.
2. Description of the Related Art
The adverse effects of exhaust by-products resulting from the operation of internal combustion engines have been known for some time. Numerous illnesses and deaths have occurred as a result of excessive atmospheric pollution due to motor vehicle operation in heavily populated areas. As a result, a great deal of research has gone into the development of some means of reducing or eliminating these pollutants. A number of different systems and principles were developed. The most effective has been the catalytic converter that is now installed in the exhaust systems of most motor vehicles. These catalytic converters use rare earth elements and precious metals, such as platinum, palladium, and rhodium, to catalyze the oxides of nitrogen, carbon monoxide, and unburned hydrocarbons in the untreated exhaust of an internal combustion engine without being consumed themselves.
While this system has proven quite effective in reducing air pollution, no catalytic converter or other exhaust treatment is one hundred percent efficient. There are still some untreated exhaust by-products that escape from the exhaust of any internal combustion engine. The overwhelming majority of such untreated exhaust by-products is dissipated into the atmosphere, where their relatively tenuous dispersal does little or no harm. However, it is a different matter when internal combustion engines are operated within an enclosed area, such as a vehicular tunnel, parking garage, etc. Even the relatively small amounts of untreated exhaust residue escaping from the operating vehicles can result in an excessive buildup of pollutants in the enclosed space, unless something is done to reduce those pollutants.
Accordingly, various efforts have been made to reduce exhaust pollution in enclosed areas. Perhaps the most common means used is the installation of large fans to draw the air (and pollutants therein) from the enclosed space for dissipation in the atmosphere, accompanied by fresh air drawn in or blown in by the fans. While this may suffice to reduce pollution within the enclosed area to an acceptable degree, the fact remains that the pollutants remain in the atmosphere outside the enclosed area.
Further efforts have been made to reduce vehicular pollution in enclosed areas by installing various devices to catalyze the pollutants or to filter them from the air. While these efforts are commendable, these systems either release the treated by-products into the air or capture the untreated pollutants in filters that must be cleaned or changed periodically.
Japanese Patent Publication No. 8-303,200 published Nov. 19, 1996 to Ishikawajima Harima Heavy Industries describes (according to the drawings and English abstract) a system for decomposing sulfur oxides and nitrogen oxides from vehicular exhaust gases in a vehicle tunnel. The system also filters dust and removes moisture from the air.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus, a catalytic converter for confined areas solving the aforementioned problems is desired.